Tolley-Jordan L.,University of Alabama |
Tolley-Jordan L.,Jacksonville State University |
Huryn A.D.,University of Alabama |
Bogan A.E.,North Carolina State Museum of Natural science
Aquatic Conservation: Marine and Freshwater Ecosystems | Year: 2015
The highest worldwide diversity of snails in the family Pleuroceridae (Caenogastropoda) is found in the Mobile River Basin, Alabama, USA. Here 76 species of pleurocerids have been described and 31 species are now considered extinct due primarily to impoundments in the Alabama River Basin. Of the major basins, only the mainstem of the Cahaba River remains free-flowing and so provides a refuge for pleurocerid diversity. Using collections, descriptions, and museum vouchers, the impact of changing land-use on pleurocerid diversity was explored in the Cahaba River Basin. Decadal scale (10 to 20 years) and century scale (70 to100 years) changes in snail diversity within the Cahaba River were determined using information on species distributions based on historical (1880-1940) collections and from 1992, and 2005-2006 surveys. Before 1940, 20 species of pleurocerid snails were reported from the basin, but in 1992 and 2005-2006, only 15 species were recovered. Conversion of the lower portion of the Cahaba River Basin from forest to agriculture before 1940, followed by silviculture and severe downcutting of the channel from headcutting, may have caused the loss of these species. However, two species historically recorded in the basin are thought to be erroneous identifications and reflect the necessity of a complete taxonomic revision of this group. No basin-wide changes in species richness and composition were detected between 1992 and 2005. Declines in richness among several reaches, however, resulted in the population fragmentation of five species which were reflected in differences in mean richness at the catchment scale. A significant, negative relationship between richness and urban cover between surveys best explained species losses. Despite taxonomic difficulties, these results indicate that land-use conversion during the last century has had significant, adverse effects on pleurocerid diversity. Continued threats are expected given the projections of increasing human population density for the south-eastern USA which may lead to further land-use alterations and instream modifications. © 2014 John Wiley & Sons, Ltd.
Schrand B.E.,Xavier University |
Schrand B.E.,University of Miami |
Stobart C.C.,Xavier University |
Stobart C.C.,Vanderbilt University |
And 3 more authors.
Southeastern Naturalist | Year: 2011
In birds, sex is determined by the allocation of sex chromosomes. We used molecular techniques to determine the sex of Mimus polyglottos (Northern Mockingbird) nestlings in Cincinnati, OH and Raleigh, NC. We found an overall male-biased sex ratio in the Cincinnati population and a female-biased sex ratio in the Raleigh population. In Cincinnati, the male-biased sex ratio was more pronounced early in the breeding season than later in the breeding season. Male nestlings were heavier than female nestlings and may require greater parental investment. In many avian species, female offspring are more likely to disperse, making them less likely to compete with parents and siblings for local resources in future seasons. This may explain why the Raleigh population with greater nesting population density overproduced female offspring.
Raske M.,North Carolina State University |
Raske M.,Animal Medical Center |
Lewbart G.A.,North Carolina State University |
Dombrowski D.S.,North Carolina State University |
And 3 more authors.
Journal of Zoo and Wildlife Medicine | Year: 2012
Ectothermic vertebrates are a diverse group of animals that rely on external sources to maintain a preferred body temperature. Amphibians and reptiles have a preferred optimal temperature zone that allows for optimal biological function. Physiologic processes in ectotherms are influenced by temperature; these animals have capabilities in which they make use of behavioral and physiologic mechanisms to thermoregulate. Core body, ambient air, body surface, and surface/water temperatures were obtained from six ectothermic species including one anuran, two snakes, two turtles, and one alligator. Clinically significant differences between core body temperature and ambient temperature were noted in the black rat snake, corn snake, and eastern box turtle. No significant differences were found between core body and ambient temperature for the American alligator, bullfrog, mata mata turtle, dead spotted turtle, or dead mole king snake. This study indicates some ectotherms are able to regulate their body temperatures independent of their environment. Body temperature of ectotherms is an important component that clinicians should consider when selecting and providing therapeutic care. Investigation of basic physiologic parameters (heart rate, respiratory rate, and body temperature) from a diverse population of healthy ectothermic vertebrates may provide baseline data for a systematic health care approach. Copyright © 2012 by American Association of Zoo Veterinarians.
Smith D.R.,U.S. Geological Survey |
McRae S.E.,U.S. Fish and Wildlife Service |
Augspurger T.,U.S. Fish and Wildlife Service |
Ratcliffe J.A.,North Carolina Natural Heritage Program |
And 3 more authors.
Freshwater Science | Year: 2015
We used a structured decision-making process to develop conservation strategies to increase persistence of Dwarf Wedgemussel (Alasmidonta heterodon) in North Carolina, USA, while accounting for uncertainty in management effectiveness and considering costs. Alternative conservation strategies were portfolios of management actions that differed by location of management actions on the landscape. Objectives of the conservation strategy were to maximize species persistence, maintain genetic diversity, maximize public support, and minimize management costs. We compared 4 conservation strategies: 1) the 'status quo' strategy represented current management, 2) the 'protect the best' strategy focused on protecting the best populations in the Tar River basin, 3) the 'expand the distribution' strategy focused on management of extant populations and establishment of new populations in the Neuse River basin, and 4) the 'hybrid' strategy combined elements of each strategy to balance conservation in the Tar and Neuse River basins. A population model informed requirements for population management, and experts projected performance of alternative strategies over a 20-y period. The optimal strategy depended on the relative value placed on competing objectives, which can vary among stakeholders. The protect the best and hybrid strategies were optimal across a wide range of relative values with 2 exceptions: 1) if minimizing management cost was of overriding concern, then status quo was optimal, or 2) if maximizing population persistence in the Neuse River basin was emphasized, then expand the distribution strategy was optimal. The optimal strategy was robust to uncertainty in management effectiveness. Overall, the structured decision process can help identify the most promising strategies for endangered species conservation that maximize conservation benefit given the constraint of limited funding. © 2015 by The Society for Freshwater Science.
Zheng W.,North Carolina State University |
Schweitzer M.H.,North Carolina State Museum of Natural science
Methods in Molecular Biology | Year: 2012
The preservation of microstructures consistent with soft tissues, cells, and other biological components in demineralized fragments of dinosaur bone tens of millions of years old was unexpected, and counter to current hypotheses of tissue, cellular, and molecular degradation. Although the morphological similarity of these tissues to extant counterparts was unmistakable, after at least 80 million years exposed to geochemical influences, morphological similarity is insufficient to support an endogenous source. To test this hypothesis, and to characterize these materials at a molecular level, we applied multiple independent chemical, molecular, and microscopic analyses to identify the presence of original components produced by the extinct organisms. Microscopic techniques included field emission scanning electron microscopy, analytical transmission electron microscopy, transmitted light microscopy (LM), and fluorescence microscopy (FM). The chemical and molecular techniques include enzyme-linked immunosorbant assay, sodium dodecyl sulfate polyacrylamide gel electrophoresis, western blot (immunoblot), and attenuated total reflectance infrared spectroscopy. In situ analyses performed directly on tissues included immunohistochemistry and time-of-flight secondary ion mass spectrometry. The details of sample preparation and methodology are described in detail herein. © 2012 Springer Science+Business Media, LLC.